Thyroid Disorders in the Elderly

(Great Britain—The Practitioner, March 1999, p. 214.) Approximately 6 percent of elderly persons have hypothyroidism and 2 percent have hyperthyroidism. Diagnosis of these conditions is frequently missed or delayed in older persons because of an obscured presentation or altered clinical course. Thyroid function tests may be affected by malnutrition, diabetes mellitus, cardiac conditions, cerebrovascular disease and other conditions that are common in old age. Drug therapy for other medical conditions may interfere with the thyroid tests or mask signs and symptoms of thyroid disorders. Hypothyroidism may be idiopathic or autoimmune, caused by previous surgery or use of radioactive iodine or drugs, including amiodarone. The signs and symptoms of hypothyroidism may be subtle or may be considered part of normal aging. Unexplained hyponatremia, anemia, macrocytosis or elevations of creatinine phosphokinase or lactate dehydrogenase should raise suspicions of hypothyroidism. Hyperthyroidism in elderly patients may present as weakness, breathlessness, anxiety, cardiac failure or atrial fibrillation. Weight loss, anorexia, confusion and lethargy may also be presenting symptoms. Goiter may be detected in up to one half of cases, depending on the etiology and ease of palpation of the gland.

Is Celiac Disease Underdiagnosed?

(Great Britain—The Practitioner, April 1999, p. 275.) Although celiac disease has been regarded as relatively rare in adults (prevalence of one case per 1,000 population), recent studies suggest that the prevalence may be as high as one case per 150 population, with many subclinical and unrecognized cases in adults. The disease results in sensitivity to gluten that leads to a range of signs and symptoms. In addition to the classic gastrointestinal upsets, celiac disease can cause hypoplasia of dental enamel, osteoporosis, peripheral neuropathy, infertility, miscarriages, iron deficiency anemia and fatigue. Up to 4 percent of patients with autoimmune thyroid condition and 4 percent of those with type 1 diabetes (formerly known as insulin-dependent diabetes) also have celiac disease. Approximately 10 to 15 percent of first-degree relatives of persons with celiac disease also have the disease. The diagnosis is confirmed by intestinal biopsy, but a screening test for serum endomysial antibodies assists in selection of patients for endoscopy. Criteria for diagnosis include remission on gluten-free diet and demonstration of symptoms and pathology consistent with the disease. The gluten-free diet that is required to control symptoms of celiac disease eliminates most cereal products and can be difficult to sustain. Support groups and dietitians may greatly assist patients and their families.

Pterygium

(Canada—Canadian Family Physician, March 1999, p. 616.) Pterygium (from the Greek word “pterygos,” meaning wing) refers to a degenerative triangular lesion of the conjunctiva. Pterygia begin in the corneoscleral junction and extend on to the cornea. The lesions may be hereditary and may be associated with exposure to dry, dusty environments. Etiologic factors may include damage to fibroblasts or focal corneal drying secondary to tear film abnormalities. The lesions are usually treated with excision, but the recurrence rate is high, up to 75 percent. The addition of a radiomimetic or chemotherapeutic agent at the time of surgery may reduce the risk of recurrence. Use of corneal autografts also significantly reduces the rate of recurrence.

Dengue Fever

(Australia—Australian Family Physician, April 1999, p. 319.) Dengue fever has become the leading health problem caused by arboviruses. In humans, the virus is usually transmitted by the Aedes aegypti mosquito, which is found throughout the equatorial regions. Urbanization provides ample opportunities for the mosquito to live indoors, where it lays eggs in water-filled containers. Several household members may be bitten during any single feeding session. Clinical dengue fever begins with sudden onset of high fever, myalgias and retro-orbital headache that typically increases with eye movement. Patients may also experience a metallic taste, minor bleeding problems and rash, particularly at the conclusion of the illness. Severe hemorrhage and encephalitis are rare complications. Dengue hemorrhagic fever may develop in children and adolescents, and can lead to death through hemorrhage and intravascular volume depletion. The diagnosis of dengue fever is clinical, supported by the laboratory finding of a rise in specific IgM titers. Treatment is symptomatic and supportive. Public health measures to control mosquitoes and relieve overcrowding are essential to prevent further spread of dengue fever.